The article "Weather Singularities over Alaska?" by Jan Curtis of the Alaska Climate Research Center (21 December 2001) on John Daly’s website "Still Waiting for Greenhouse" includes two interesting comments. "So if there isn’t a physical explanation for these singularities, statistics might be able to answer this mystery" and "For a singularity to exist, a physical mechanism is needed."   The author speculates on reduction of solar heating in winter, an expansion of cold dense air and a subsequent surge across Alaska as a cause. "With the release of this pool of cold air over the Arctic, a temporary temperature rebound occurs. After about a month, this scenario is repeated and a month later repeated again." A reasonable speculation, but it simply describes the pattern of Rossby Waves. A 4 to 6 week cycle that causes shifts in the weather as the waves migrate through the mid-latitude regions. Changes in the amplitude of the Waves cause variation in the severity of the changes – a feature overlooked in the climate pattern of the last few years. The amplitude change results in increased variation yet the statistical focus remains close to long term averages. We have to distinguish between increased variability of cyclical events and real singularities. We also have to understand the distortion to hemispheric and global temperature averages created by the Wave pattern.

Current weather patterns have extremes of hot and cold round the world – what appear to be singularities. The pattern is most noticeable in the Northern Hemisphere because of differences in land/water ratios, especially in the middle latitudes. Advocates of global warming due to human actions use the patterns as support for their argument. The problem is the Rossby Waves offer a natural explanation.

Climatology is a generalist subject struggling with the dominance of specialization. It requires a wide grasp that links all the factors, but that’s a great challenge. Computer models offered a chance to handle large volumes of information and make many linkages, but General Circulation Models (GCM) only illustrate the limitations and underline the linkage problem.

GCMs are mathematical models comprised of linked mathematical models, because in most cases we don’t know the natural linkages. Consistent failure of the model predictions is no surprise. Attempts to fix them by simply adding a variable with no evidence, as with sulfates, only makes it worse. There is a scientific responsibility with the assumptions, and testing of the models, generally not fulfilled. A classic example of the problem is the inability to determine the effect of clouds. There is a social responsibility incurred when you present the models to the public as accurate portrayals of reality with valid predictions. Unfortunately, many people are not accepting either responsibility.

Specialization also creates difficulties, especially when an individual study or phenomenon is applied inappropriately to a multitude of problems. Information is taken out of context, with no understanding of the scientific nature of the original theory, especially the limitations set by the assumptions. One analogy is that each specialist has a piece of the jigsaw puzzle, but we don’t have the box top. Indeed, we don’t have the corners or most of the edge pieces. El Niño/La Niña are not new phenomena. Inca farmers and Spanish sailors were familiar with their occurrence centuries ago. Sir Francis Drake learned of their existence and sailed the ‘Spanish course’ in 1578-79, a strong El Niño year. However, when they were ‘discovered’ in the 1980s they were applied inappropriately to almost every other phenomena. It was the latest weather fad that explained everything.

Environment Canada has applied El Niño/La Niña patterns to long-term forecasts with very little success. In 1992 they predicted hot dry conditions for western Canada: it was the coolest wettest summer on record, a true singularity. Mount Pinatubo erupted in 1991 and caused global cooling in 1992. The mean summer position of the Polar Front was several hundred kilometers south of the long term summer average latitude. Winnipeg, Manitoba had summer temperatures similar to the climate normal for Churchill, 800 km north on Hudson Bay. Two factors are important. Cold air is denser and heavier than warm air and determines what happens when the two meet. The patterns of climate and weather phenomena differ if the global trend is toward cooling or warming. So, as the mean position of the Polar front changes with global temperature change the pattern of weather in the middle latitudes is different.

Most researchers now accept the reversals of ocean currents in the Pacific on the climate and weather of some regions of the earth. Forecasters in Australia and the United States monitor the Southern Oscillation Index (SOI) closely because of its significance to their agricultural conditions. The SOI measures the pressure difference between Darwin, Australia and Tahiti that indicates the direction of subtropical winds. There are no clear explanations for the changes in pressure. Vague statements about temperature changes and upwelling of cold water litter the literature but beg the question of cause.

Dr Theodor Landscheidt has developed a model to predict El Niño events based on solar activity. He predicts a return of El Niño in the late summer of 2002 ± 6 months. One prediction is exciting, but not definitive. A few more and it becomes a valuable tool for agriculture in large areas of the world. Correlation of activities on the sun with atmospheric conditions on earth is not proof either. Unless there is a mechanism to explain the correlation researchers usually ignore them.

The sun is ignored as a cause of climate change for four main reasons.

  Absolute measurements of changes in solar radiation are limited in number and length.

  Measures that exist record very small changes.

  Generally only changes in the electromagnetic spectrum are considered.

  There is no clear mechanism to explain correlation between solar activity and climate change.

Studies, mostly those using GCMs, suggest variability of the electromagnetic spectrum explains about 30 percent of recent instrumentally measured temperature change. Arguments about variation in output of electromagnetic energy, losses in transmission through space and in the atmosphere and accurate determination of energy imparted to the surface fill the literature Most accept the sun as the sole source of energy for the earth yet its effect is somehow dramatically reduced in the final analysis. Instrumental measurements are limited, but the few that exist span periods of solar maximum and minimum. Other secondary sources indicate greater variability. Astrophysicists, who define the sun as a variable star, show high correlation between global temperature and solar variations.

The instrumental records do show small changes. However, a major mistake is assuming a change of 0.14 percent is an insignificant part of 100 percent. Theoretical calculations indicate that a 6 percent change in solar energy can explain all the temperature variation in the Earth’s history. If true, it means a fractional change is significant.

These measurements are of the electromagnetic spectrum. There are measurements of the corpuscular radiation, more commonly known as the solar wind, but these are not generally considered as sources of climate change. They are inferred as a cause because most studies, including those of Landscheidt, Labitzke, Baliunas and others show relationships between the 11 year Hale, 22 year Schwab, and 90 year Gleissberg sunspot cycles.

Why are these studies ignored? Lack of interdisciplinary study demanded by climatology research is one explanation. Lack of understanding of mechanisms is another. A subconscious, occasionally conscious, desire to attribute climate changes to human activities is another. As Richard Lindzen said about global warming, the consensus was reached before the research had even begun.

Part of the difficulty in determining the mechanism, beyond defining the amount of effect, is in an unwritten assumption. Researchers on both sides of the issue of solar effect usually assume that a change in solar output results in a measurable change in all parts of the earth. There is allowance for a delayed effect due to local conditions, sometimes for extended periods, for example, when the cause is a change in slow cycles such as deep ocean circulation.

The assumption appears logical if you assume the sun, especially the electromagnetic radiation, is the source of all energy and the only solar output to cause climate change. Geothermal energy is not considered. Heat entering the atmosphere directly from volcanic eruptions is minor compared to the annual solar energy. However, heat injected into the oceans from active volcanoes and the vast ocean ridges is continuous, unmeasured and circulated for long periods.

The solar wind emanates from the sun with varying intensity. Ionized particles strike the outer layers of the atmosphere causing a compression on the upwind side and a large tail downwind. The effect is most clearly seen in the magnetosphere. If the wind causes distortion, then variation in the strength of the wind must cause variation in the amount. Pressure on one layer will cause pressure on underlying layers right down to through the stratosphere to the troposphere. There must be internal adjustments within each layer besides the transmission of energy. Compression must result in horizontal adjustments of gases within the layer.

Environment Canada’s assumption that El Niño affects Canadian climate is partly due to jumping on the climate fad bandwagon. However, it’s also due to an apparent connection between weather changes in the subtropical regions where El Niño/La Niña are active and changes in the middle latitudes (35° to 65°), the zone influenced by the Polar Front, and the Westerlies or Circumpolar vortex. They see changes in El Niño/La Niña and changes in Canadian weather and assume a cause and effect relationship.

El Niño/La Niña are now understood as the major mechanisms of climate in the subtropics. They generally operate between 15° and 35° affecting climate in countries bordering the Pacific Ocean in those latitudes. The reversal of surface currents are related to reversals of the relatively weak upper level subtropical winds. These appear to correlate with solar cycles as Labitzke has shown. This connection is the basis of Landscheidt’s prediction.

The Polar Front separates cold polar air from warm tropical air and marks distinct climate differences. The Front is the zone of Zero Energy Balance, that is incoming energy equals outgoing energy. In the polar air there is a deficit of energy while there is a surplus in the tropical air. The seasonal boundaries of the Front coincide with many natural features including the snowline and limits of vegetation zones such as the tree line.

The migration of the Front dictates the seasonal weather which is then modified by the Rossby Waves that undulate from west to east with the westerly winds. The Waves are caused by sinuosity that forms in the Circumpolar vortex. The sinuosity varies from low amplitude or zonal waves to high amplitude or meridional waves. The weather patterns associated with each pattern are distinctly different.

Zonal flow has low amplitude waves with winds generally from the northwest in winter on the polar side of the Front and southwesterly on the subtropical side. This pattern migrates north and south with the seasonal migration of the Front. Weather tends to alternate on a four to six week cycle as the waves migrate from west to east. Weather is relatively stable with reduced severe weather as cold air doesn’t intrude well south.

Meridional flow has high amplitude waves with winds predominantly north on the polar side and south on the subtropical side. Cold air pushes well south and warm air well north often setting records. Severe weather increases as greater contrasts of temperature occur across the Front. Weather is unstable as it shifts from warm to cold on the four to six week cycle. When the waves become very deep they tend to stall and weather patterns persist. For example, a dry period of five weeks doubles to a worrisome eight to twelve weeks. This extreme meridional pattern accounts for the seasonal singularities identified in the Curtis article on Alaska.

The important point is that the flow of the circumpolar vortex does not reverse, unlike the subtropical winds. However, they are affected as flow changes between zonal and meridional.

Apparently, when the solar wind increases pressure on the atmospheric layers the increase causes the subtropical winds to stop or even reverse. The circumpolar vortex becomes increasingly meridional often until blocking occurs.

So we have two phenomena occurring at the same time caused by changes in the solar wind; reversals in the upper level winds creating El Niño/La Niña and changes in the pattern of Rossby Waves of the circumpolar vortex. They create different weather in different latitudes but it is not a cause and effect relationship.

Another effect of the waves, especially when blocking occurs, is to distort the average temperatures for different regions including the Northern Hemisphere and possibly the world.

Northern Hemisphere weather stations are concentrated in northeastern North America and Western Europe. Meridional or zonal patterns can persist for decades and dominate large regions. A variety of different temperature averages can develop that reflect the wave pattern and location of the thermometers, not the actual average. For example, if a strongly meridional pattern allows warm air well north in eastern North America and cold air well south in western North America then the continental average is higher than in the reverse condition. Distortion is accentuated if the wave pattern is allowing warm air to dominate eastern North America and Western Europe.

The basic pattern of the circumpolar vortex, or Rossby Wave sequence, is apparently determined by changes in the solar wind. However, this is modified in the Northern Hemisphere, particularly in North America, by latitude of the Polar Front. The Rocky Mountains are higher in British Columbia than in the United States, and higher and wider as you move toward Alaska.

The downwind pattern is affected by the point at which the vortex crosses the Mountains. It is also affected by the season, because the vortex is lower in the winter than the summer. The pattern of weather in Alberta, Canada, immediately downwind of the Mountains reflects this disturbance effect.

About the Author

Dr Tim Ball obtained his Ph.D from Queen Mary College, University of London, England. His thesis was the reconstruction of climate from 1714 to 1982 using the meteorological journals and daily records of the Hudson's Bay Company. There is a chapter on this work in Climate Since A.D 1500 edited by R. Bradley and P.Jones. He taught for 30 years at the University of Winnipeg and now runs an environmental consulting company in Victoria, British Columbia.

He has many publications including articles in Climatic Change and the Journal of Climatology. A joint authorship book with Dr. Stuart Houston on forgotten naturalists of the 18th century fur trade in North America is currently in press at McGill/Queens University Press. He has written a monthly column
called "Weather Talk" in Country Guide, the largest circulation farm journal in Canada for 12 years.